Optical densitometers are well known in the graphic arts and are generally used to determine the optical density of a color swatch or an area of a sheet of material which is characterized by one of the basic colors cyan, magenta, or yellow. In the prior art, such optical densitometers have been static densitometers and have usually been composed of a light source, a rotatable color light filter means, and a photosensitive device. The user knew what color he was examining and therefore rotated the correct light filter into position and thereafter physically moved the densitometer to a position to focus the white light on the color swatch or area of the sheet to be examined. The light of course was reflected from the swatch and read by the photosensitive device to provide an electrical signal indicative of the opitcal density being read. The present device goes beyond the static densitometer because it is used in a scanning mode; that is, it looks at many swatches, one after another, and determines virtually instantaneously which of the basic colors is predominant on the swatch and the optical density thereof. The user need not know what colors are being examined as was true in the prior art. As explained in my copending patent application, Ser. No. 951,444entitled "Color Monitoring System For Use In Creating Colored Displays", filed Oct. 13, 1978, the signals from the present scanning head are compared one with another and the greatest signal indicates the predominant basic color (if the color swatch under examination is a swatch of a basic color; i.e., cyan, magenta or yellow, then the signals will readily indicate which basic color is being examined of the swatch or area being monitored. The optical density of the predominant color is also determined. The foregoing is possible because each of the color filter photosensitive element arrangements (one each is located in a different one of the housing apertures) is particularly associated with a different one of the basic colors cyan, magenta and yellow, so that each of the signals produced by the photosensitive elements is indicative of the optical density of its associated basic color. These signals are produced simultaneously and hence the present head provides information in one viewing of a swatch which indicates the identity of the basic color and its optical density.